<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .menu {
            position: absolute;
            left: 0;
            top: 0;
            bottom: 0;
            width: 200px;
            padding-top: 100px;
            font-family: Consolas,arial,"宋体";
            background-color: #ccc;
        }

        .menu a {
            display: block;
            height: 40px;
            margin: 0 0 1px 2px;
            padding-left: 10px;
            line-height: 40px;
            font-size: 14px;
            color: #333;
            text-decoration: none;
        }

        .menu .cur {
            color: #000;
            background-color: #fff !important;
        }
    </style>
</head>
<body>
<div class="menu">
    <a href="./">1、默认效果</a>
    <a class="cur" href="index2.html">2、jQuery版本</a>
    <a href="index3.html">3、回调函数</a>
    <a href="index4.html">4、自定义方法</a>
</div>
</body>
</html>